In this unit we explored the relationship between the depth of Earth and pressure and temperature. We examined the density of differing layers. We are able to create a trendline of depth to density/pressure.

We also know about the chemical and physical composition (make-up) of each layer of the earth.

Review: Composition of the Earth

As the solar system continued to coalesce, the planets - including Earth - were undergoing their own organization, as dictated by the materials of which they were composed and their position relative to the sun and each other. The goal of this unit is to examine our current understanding of the materials that make up the Earth, how these substances are arranged, and the evidence that supports this theory.

Essential Questions:

How can we use current scientific understanding of physics, chemistry, geology, and biology to describe the formation of the layers of the earth, including the geosphere (crust, mantle, core), hydrosphere, and atmosphere?
How does modern technology (analysis of Earth's magnetic field, composition of meteorites, and seismic waves) provide evidence to support the model of the physical composition of Earth's layers?

Key Words:

Asthenosphere - the upper layer of the earth's mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur
Core - the central or innermost portion of the Earth, lying below the mantle and probably consisting of iron and nickel
Crust - the outermost portion of the Earth (the surface), lying above the mantle and consisting of a great variety of igneous, metamorphic, and sedimentary rocks
Density - a measure of mass per volume
Fact - any observation that has been repeatedly confirmed and accepted as true
Geology - the science that deals with the earth's physical structure and substance, its history, and the processes that act on it
Geosphere - the solid part of the Earth consisting of the crust and outer mantle
Hydrosphere - all of the Earth's water, including surface water (water in oceans, lakes, and rivers), groundwater (water in soil and beneath the Earth's surface), snow cover, ice, and water in the atmosphere, including water vapor
Lithosphere - the rigid outer part of the earth, consisting of the crust and upper mantle
Magnetic Field - a place in space near a magnet or an electric current where a physical field is created from a moving electric charge that creates force on another moving electric charge
Mantle - the part of the Earth between the core and the crust
Meteorite - a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the planet's atmosphere and impact with the planet's surface
Seismic Waves - a wave of energy that is generated by an earthquake or other Earth vibration and that travels within the Earth or along its surface
Silicates - compounds containing silicon and (usually) oxygen
Theory - a coherent group of propositions formulated to explain a group of facts or phenomena in the natural world and repeatedly confirmed through experiment or observation

IMAGES CREATED BY GAVS OR OPENSOURCE